The present invention relates broadly to a sealing construction for providing a fluid seal intermediate a pair of opposed, mating parts or structures, and more particularly to an interference-fitting retainer gasket construction adapted to provide a fluid seal between such mating structures as aircraft wings and fuel access panels wherein the access panel is mounted to the underside of the wing skin.
Gaskets of the type herein involved are employed in a variety of sealing applications, such as in commercial, industrial, or military equipment, vehicles, or aircraft for compression between the opposing or faying surfaces of a pair of mating parts or structures to provide a fluid-tight interface sealing thereof. In basic construction, such gaskets are typically are formed of a relatively compressible, annular seal member having a central aperture configured for registration with the corresponding margins of the surfaces.
The seal member typically is supported by an annular metal or plastic retainer. In such an arrangement, the retainer is stamped or molded to conform to the surface geometry of the mating structures, with the seal member being molded-in-place in a groove formed into one or both sides of the retainer, or about the inner and/or outer periphery of the retainer to form an integral gasket structure. Representative retainer-supported gaskets are shown, for example, in U.S. Pat. Nos. 3,195,906; 3,215,442; 3,259,404; 3,578,346; 3,635,480; 3,720,420; 3,746,348; and 4,026,565, and are marketed commercially by the O-Seal Division of Parker-Hannifin Corporation, San Diego, Calif., under the tradename xe2x80x9cIntegral Seals.xe2x80x9d
In service, the gasket is clamped between the mating surfaces to effect the compression and deformation of the seal member and to develop a fluid-tight interface with each of those surfaces. Most often, the compressive force is provided using a circumferentially spaced-apart arrangement of bolts or other fastening members, each of which is received through an indexed pair of bores formed within the surfaces. Depending upon the geometry of the gasket, the fastening members also may be indexed through corresponding apertures formed within the seal or retainer member of the gasket.
Particularly for applications which require the positioning of the gasket between the underside of a structure, such as and aircraft wing, and a mating structure, such as a fuel access door, it sometimes is problematic for the installer to maintain a proper alignment of the parts. Heretofore, this problem has been addressed either by using epoxy or other formed-in-place gaskets or caulks, or with various clip or plastic snap arrangements to secure the gasket in place during mounting. As to these formed-in-place gaskets or caulks, their application requires considerable training and skill, and often is an involved processes requiring several hours for completion. Alternatively, the clips and snaps employed are sometimes difficult to install and/or to remove.
In view of the foregoing, it is apparent that improvements in the construction of retainer gaskets for aerospace and other applications would be well-received by industry. A preferred gasket construction would be economical to manufacture, but also would exhibit reliable sealing performance. Such a gasket additionally would facilitate installations, such as in the underside of aircraft wings, requiring that the gasket be mounted in an orientation which complicates the alignment of the mating parts.
The present invention is directed to a retainer gasket construction particularly adapted for providing a fluid-tight seal about a periphery intermediate an opposing pair of interface surfaces such as may be found between an aircraft wing and a mating fuel access door assembly. The gasket is of a closed geometric shape and includes a generally planar, preferably metal, retainer and an elastomeric member which is supported on the retainer. The elastomeric member is molded or otherwise formed as having a generally-annular sealing element which may be configured as one or more seal beads, and a retaining element which is generally upstanding relative to the sealing element as extending axially out of the plane thereof. The retaining element may be molded integrally with the sealing portion, and configured as having a radial surface adjacent the sealing element which is of a diametric extent sized to interfere with the periphery. Accordingly, the retaining element may be interference fit, depending upon the configuration of the assembly, on an inner or outer diameter of the periphery to be sealed to thereby hold the gasket in place irrespective of the orientation of the mating parts, and to provide positive location and alignment as the parts are being joined.
To facilitate the mounting of the gasket about periphery, the radial surface of the retaining element optionally may be formed as having a radiused or chamfered edge or other portion to effect a radial inward or outward deflection of the retaining portion as it is fitted within or around the periphery. As the gasket relaxes or otherwise returns to its original shape, the retaining element exerts a reaction force against the periphery to frictionally hold the gasket thereon. The retainer provides the rigidity necessary for the development of the reaction force, and further functions to resist torsional forces which otherwise would have the tendency to deform the gasket shape. However, the retainer also may be made sufficiently thin so as to be deflectable to accommodate complex curvatures between the mating surfaces.
Advantageously, the gasket construction of the present invention may be adapted for use with various sealing assembly configurations, and particularly may be configured to be mounted about either an inner or outer diameter of the periphery. Moreover, by virtue of the provision of the retaining portion, the gasket also is able to accommodate variations in tolerances between the mating parts without damage to itself or to the parts.
The present invention, accordingly, comprises the apparatus possessing the construction, combination of elements, and arrangement of parts which are exemplified in the detailed disclosure to follow. Advantages of the present invention include a sealing gasket construction which exhibits reliable sealing properties and torque retention with a minimum of compression set. Additional advantages include a gasket construction which is economical to manufacture, and which is self-locating, retaining, and aligning to both simplify and expedite installation. These and other advantages will be readily apparent to those skilled in the art based upon the disclosure contained herein.